The invention relates to a rotary pressure, particularly for the manufacture of tablets, with a driven rotor and at least one pressure roller unit which is detachably secured to a bearing device by means of a retaining device.
A generic rotary press, such as that disclosed in DE 197 05 094 C1, for example, has a rotarily driven rotor which rotates in an essentially horizontal plane and supports a multiplicity of die pairs, each of which consists of an upper die and a lower die, which are adjustable relative to each other. At a predetermined point on the circumference of the rotor the material to be processed and the material to be pressed into a tablet are poured by means of a filling device into the intermediate space between the upper die and the lower die. When the die pair thus filled is moved by the rotation of the rotor in its circumferential direction, the two dies are moved towards each other by control cams and are then fed to at least one pressure roller unit lying upstream in the circumferential direction of the rotor, in which unit they are pressed against each other with pressure, as a result of which the material is compressed to form the tablet. The dies then enter an extraction station lying upstream in the circumferential direction of the rotor, in which station the dies move apart and the tablet is extracted and discharged.
The method process shown relates to the manufacture of the tablet from a uniform material, i.e. a so-called 1-layer tablet. As a variant of the procedure, additional pre-pressing of the material may be provided, for which purpose a further pressure roller unit is then used which is arranged between the filling device and said pressure roller unit.
A pressure roller unit may have either a pair of pressure rollers or even an individual pressure roller.
If a multi-layer tablet is to be manufactured from two or more different materials, a 1st material is first poured into the intermediate space between the dies by means of a 1st filling device, whereupon this 1st material is pre-compressed by means of a 1st pressure roller unit. A 2nd material is then poured into the remaining intermediate space between the dies by means of a 2nd filling unit, then compressed by means of a 2nd pressure roller unit. If necessary further layers from the same and other materials may also be provided. All the materials are compressed to form the tablet, which is then extracted. In this case a multiplicity of work stations, namely at least two filling devices, at least two pressure roller units and the extraction station are therefore arranged distributed around the circumference of the rotor.
A further, essentially different configuration of the work station is required for manufacturing a so-called core-coated tablet, where a prefabricated core of a 1st material is coated in a lower and upper layer of a 2nd material. In all cases pre-pressing of the material may also be provided and different filling devices are used, according to the nature and quantity of the material to be processed.
In order to adapt the rotary pressure to the type of tablet required by the user (for example single-layer tablet, bi-layer tablet, tri-layer tablet, core-coated tablet, either with or without pre-pressing), and also to the type of material to be processed, the user must align and install the individual work stations in a certain mutual arrangement relative to the rotor, for which purpose an expensive conversion of the rotary press is required, resulting in long down times of the rotary press.
The objective of the invention is to provide a rotary pressure of the type mentioned whose conversion for adaptation to a different type of tablet production is facilitated.